#include <stdio.h>
 main()
{	     	  
   int year;
   printf("please input year:");
   scanf("%d",&year);
   if(year%4==0 && year%100!=0 || year%400==0)
   {	     	  
       printf("%d  OK!\n",year);}
   else
   {	     	  
       printf("%d  NO!\n",year);
   }
}